1. Field of the Invention
This invention relates to apparatus for controlling gimbal-stabilized platforms and the like and, more particularly, to such apparatus incorporating a trackball as a user-input device.
2. Description of Related Art
Gimbal stabilization of support platforms for cameras and the like is commonly used where the camera in operation is being transported by a vehicle, such as aircraft, boats or ground vehicles, and stabilization is needed to obtain clear images. Examples of such applications include remotely piloted aircraft (drones) where a video camera is used to provide signals over a video link to an observer in another aircraft or on the ground, infrared sensors mounted on helicopters for providing images to the pilot for enhanced night vision operations, movie cameras at motion picture production sites, boom-mounted cameras at sporting events and the like for following a football or golf ball in flight, and numerous similar applications. In the past, gimbal control has commonly been effected through the use of spring-loaded "joy sticks". A typical joy stick comprises a short, generally vertically oriented stick having a tip which may be manipulated by the thumb and fingers of an operator in two orthogonal directions to provide "x" and "y" input to the system. Joy sticks are commonly used as a control mechanism in video and computer games.
In computer jargon, a trackball may be commonly used as a substitute for a mouse, which is a cursor control mechanism. In the present invention, a trackball is combined with a mode selection switch to replace spring-loaded joy stick control methods of gimbal control which are known in the prior art.